CABT Certified Associate in Biomedical Technology Exam — Questions and Answers

Question 1: A biomedical technologist notices that an ultrasound image shows a bright echo directly behind a highly reflective structure. This is best described as:

Reverberation artifact (Correct answer)
Posterior acoustic enhancement
Acoustic shadowing
Mirror image artifact

Correct answer: Reverberation artifact

Reverberation artifact appears as multiple equally spaced bright lines behind a strongly reflective interface due to sound bouncing back and forth.

Question 2: A nurse reports that an electric hospital bed moves very slowly when raising the head section. The biomedical technician checks voltage at the motor and finds it within spec. What should be investigated next?

The main circuit breaker amperage rating
Mechanical binding or worn drive mechanism in the bed frame (Correct answer)
The mattress weight
The nurse control panel cable

Correct answer: Mechanical binding or worn drive mechanism in the bed frame

If electrical supply to the motor is correct, slow movement points to a mechanical issue such as friction, binding, or a worn actuator/gearbox.

Question 3: What does 'CV%' (coefficient of variation) measure when validating laboratory equipment precision?

The number of measurements within acceptable range
The difference between measured and true values
The percentage of random variability relative to the mean across repeated measurements (Correct answer)
The percentage of samples that passed quality control

Correct answer: The percentage of random variability relative to the mean across repeated measurements

CV% = (standard deviation / mean) × 100, expressing random variability as a percentage of the mean to assess instrument precision.

Question 4: After replacing a fuse in a biomedical device, the new fuse blows immediately upon power-up. The technician should:

Install a higher-rated fuse to handle the load
Investigate for a short circuit or overload condition before replacing the fuse again (Correct answer)
Replace the fuse again and monitor for recurrence
Use a wire jumper temporarily until parts arrive

Correct answer: Investigate for a short circuit or overload condition before replacing the fuse again

An immediately blown replacement fuse indicates an underlying short circuit or overload condition that must be diagnosed and corrected before installing another fuse.

Question 5: What is the MOST important factor to consider when selecting assessment tools for CABT certification work?

How quickly the tool can be administered
Validity, reliability, and appropriateness for the specific context (Correct answer)
The cost of the assessment tool
Personal familiarity with the tool

Correct answer: Validity, reliability, and appropriateness for the specific context

Assessment tools must be valid (measuring what they claim to measure), reliable (producing consistent results), and appropriate for the specific context and population. These psychometric properties ensure the quality of assessment outcomes.

Question 6: A Wheatstone bridge is balanced when:

R1/R2 = R3/R4 (Correct answer)
R1 + R2 = R3 + R4
R1 - R2 = R3 - R4
R1 × R2 = R3 × R4

Correct answer: R1/R2 = R3/R4

The Wheatstone bridge is balanced (zero galvanometer current) when the ratio of resistances in each arm are equal: R1/R2 = R3/R4.

Question 7: What is the recommended action when an automated analyzer's QC result exceeds the 3-SD (3 standard deviation) Westgard rule?

Report patient results with a flag and continue
Repeat QC once and report if within 2 SD on the second run
Reject the run, investigate the cause, and do not report patient results until resolved (Correct answer)
Adjust calibration to bring QC within range

Correct answer: Reject the run, investigate the cause, and do not report patient results until resolved

A 3-SD violation (1₃s rule) indicates random error and requires run rejection, root cause investigation, and re-running QC before releasing patient results.

Question 8: A capacitor is connected in series with a resistor to an AC source. As frequency increases, what happens to the capacitive reactance (Xc)?

Xc decreases (Correct answer)
Xc remains constant
Xc becomes zero
Xc increases

Correct answer: Xc decreases

Capacitive reactance Xc = 1/(2πfC), so as frequency increases, Xc decreases.

Question 9: What is the MOST important factor to consider when selecting assessment tools for CABT certification work?

Validity, reliability, and appropriateness for the specific context (Correct answer)
How quickly the tool can be administered
The cost of the assessment tool
Personal familiarity with the tool

Correct answer: Validity, reliability, and appropriateness for the specific context

Question 10: In a biomedical device, a zener diode is used primarily to:

Amplify small signals
Rectify AC to DC
Regulate voltage (Correct answer)
Store electrical charge

Correct answer: Regulate voltage

Zener diodes operate in reverse breakdown to maintain a stable reference voltage, making them ideal for voltage regulation.

Question 11: What does the term 'double insulation' (Class II equipment) mean?

Two-phase power supply for redundancy
Two separate ground wires inside the power cord
Dual leakage current testing at twice normal voltage
Two independent layers of insulation so no grounding conductor is needed (Correct answer)

Correct answer: Two independent layers of insulation so no grounding conductor is needed

Class II (double-insulated) devices have two independent insulation barriers, eliminating the need for a protective earth connection.

Question 12: Which type of centrifuge is specifically designed to separate blood components by spinning at low speeds (400-1200 RPM)?

Blood bank centrifuge (Correct answer)
Refrigerated centrifuge
Microcentrifuge
Ultracentrifuge

Correct answer: Blood bank centrifuge

Blood bank centrifuges operate at low speeds optimized for separating red cells, plasma, and platelets without damaging fragile blood components.

Question 13: When testing total patient leakage current on an ECG monitor connected to a patient simulator, the technician should measure:

DC offset of the signal amplifier
Voltage across the chassis to ground
Current from all patient-applied parts to ground collectively (Correct answer)
Resistance of the power cord

Correct answer: Current from all patient-applied parts to ground collectively

Total patient leakage current is measured by summing the current from all applied parts (leads) to ground under worst-case conditions.

Question 14: Which class of electrical equipment relies solely on basic insulation for protection and has no grounding conductor?

Class I
Class 0 (Correct answer)
Class III
Class II

Correct answer: Class 0

Class 0 equipment relies only on basic insulation with no additional safety measure such as grounding or protective extra-low voltage.

Question 15: What is the primary function of a cell saver (autotransfusion device) during surgery?

To collect, wash, and reinfuse the patient's own shed blood (Correct answer)
To warm IV fluids to body temperature before infusion
To pump blood during cardiopulmonary bypass
To monitor real-time hemoglobin levels via pulse oximetry

Correct answer: To collect, wash, and reinfuse the patient's own shed blood

A cell saver collects blood lost during surgery, processes it by centrifugation and washing, then returns the patient's own red blood cells, reducing allogeneic transfusion requirements.

Question 16: What is the Nyquist theorem's requirement for sampling an analog signal to avoid aliasing?

Sample at least 10 times the signal frequency
Sample at the same rate as the signal frequency
Sample at least twice the highest frequency in the signal (Correct answer)
Sample at the signal's fundamental frequency

Correct answer: Sample at least twice the highest frequency in the signal

The Nyquist theorem states that the sampling rate must be at least twice the highest frequency component of the signal to accurately reconstruct it without aliasing.

Question 17: When zeroing an invasive arterial pressure transducer, the stopcock reference port should be positioned at the level of the:

Phlebostatic axis (mid-axillary line at the 4th intercostal space) (Correct answer)
Patient's feet
Level of the catheter insertion site
Top of the patient's head

Correct answer: Phlebostatic axis (mid-axillary line at the 4th intercostal space)

The phlebostatic axis approximates the level of the right atrium and is the standard reference point for zeroing hemodynamic transducers.

Question 18: In anatomical position, which directional term refers to a structure closer to the point of attachment of a limb?

Proximal (Correct answer)
Lateral
Distal
Inferior

Correct answer: Proximal

Proximal describes a position closer to the point of origin or attachment of a limb, while distal refers to farther away.

Question 19: A pulse oximeter provides an SpO2 reading by measuring the differential absorption of two wavelengths of light. Which operational principle allows the device to distinguish between arterial and venous blood?

It uses a third wavelength of light to specifically isolate and cancel out the signal from venous blood.
The device only analyzes the pulsatile component of the light absorption, which corresponds to arterial blood flow. (Correct answer)
The probe heats the tissue, which temporarily increases arterial flow for a more accurate measurement.
It measures the static (non-changing) absorption from all tissues and subtracts a baseline value.

Correct answer: The device only analyzes the pulsatile component of the light absorption, which corresponds to arterial blood flow.

A pulse oximeter identifies arterial blood by detecting the pulsatile nature of its flow, which corresponds to the heartbeat. The device measures the light absorption during both the systolic (pulse) and diastolic (no pulse) phases. The changing, or AC component, of the signal is attributed to the pulsatile arterial blood, while the constant, or DC component, is from non-pulsatile venous blood and tissue. By focusing only on the AC component, it can accurately calculate arterial oxygen saturation (SpO2).

Question 20: A syringe pump is programmed for 5 mL/hr but delivers only 2 mL/hr. Which mechanical issue is most likely responsible?

Incorrect drug concentration label
Low battery condition
Upstream occlusion alarm muted
Incorrect syringe size selected in the pump settings (Correct answer)

Correct answer: Incorrect syringe size selected in the pump settings

If the wrong syringe size is selected, the pump miscalculates the plunger travel distance needed, resulting in significant delivery errors.

Question 21: A biomedical technician services a patient warming system. Which physiological mechanism does this device support by maintaining core body temperature?

Osmoregulation
Thermoregulation (Correct answer)
Glucoregulation
Hematopoiesis

Correct answer: Thermoregulation

Thermoregulation maintains core body temperature within narrow limits (36.5–37.5°C) to ensure optimal enzymatic function and cellular processes.

Question 22: What is the role of the sinoatrial (SA) node in cardiac physiology?

It delays conduction between atria and ventricles
It controls valve opening and closing
It supplies blood to the conduction system
It initiates the electrical impulse that sets the heart rate (Correct answer)

Correct answer: It initiates the electrical impulse that sets the heart rate

The SA node, located in the right atrium, spontaneously depolarizes at 60–100 bpm, acting as the natural pacemaker of the heart.

Question 23: Which professional attribute is most valued in laboratory equipment within the CABT field?

Prioritizing personal convenience
Avoiding challenging situations
Accountability and commitment to standards (Correct answer)
Working in isolation

Correct answer: Accountability and commitment to standards

Accountability and commitment to professional standards build trust and ensure consistent, high-quality practice.

Question 24: The primary purpose of the 510(k) premarket notification process is to demonstrate that a new device is:

Approved for international distribution
Safe and effective through clinical trials
Classified as Class I exempt from regulation
Substantially equivalent to a legally marketed predicate device (Correct answer)

Correct answer: Substantially equivalent to a legally marketed predicate device

The 510(k) pathway requires demonstrating substantial equivalence to a predicate device in terms of intended use and technological characteristics.

Question 25: Which type of tissue connects muscles to bones?

Ligaments
Cartilage
Tendons (Correct answer)
Fat

Correct answer: Tendons

Tendons are strong, fibrous connective tissues that attach muscles to bones. They are crucial for transmitting the force generated by muscle contractions to the bones, enabling movement. Ligaments, in contrast, connect bones to other bones, providing joint stability.

Question 26: What is the primary anatomical difference between arteries and veins that relates directly to their physiological function?

Arteries have thicker, more muscular walls to handle high pressure from the heart. (Correct answer)
Veins are typically located deeper within the body than arteries.
Arteries contain valves to prevent the backflow of blood.
Veins have thicker, more muscular walls to withstand high pressure.

Correct answer: Arteries have thicker, more muscular walls to handle high pressure from the heart.

Arteries carry oxygenated blood away from the heart under high pressure. Their walls are thick and muscular to withstand this force and help propel blood. Veins carry deoxygenated blood back to the heart under lower pressure and have thinner walls. Many veins, especially in the limbs, contain valves to prevent blood from flowing backward due to gravity.

Question 27: Which body system is primarily involved in oxygen exchange?

Digestive system
Respiratory system (Correct answer)
Skeletal system
Nervous system

Correct answer: Respiratory system

The respiratory system is primarily responsible for the exchange of gases, specifically taking in oxygen and expelling carbon dioxide. This vital process occurs mainly in the lungs, where oxygen from inhaled air diffuses into the bloodstream and carbon dioxide from the blood diffuses into the air to be exhaled. It is essential for cellular respiration and maintaining the body's pH balance.

Question 28: A patient's ECG shows a prolonged PR interval. Which anatomical structure is most likely causing the conduction delay?

Atrioventricular (AV) node (Correct answer)
Purkinje fibers
Bundle of His
Sinoatrial (SA) node

Correct answer: Atrioventricular (AV) node

The PR interval represents the time for electrical impulses to travel from the SA node through the AV node; a prolonged PR indicates AV node delay.

Question 29: Which of the following electronic components is a semiconductor device that allows current to flow in only one direction and is often used for rectification in power supplies for medical equipment?

Resistor
Inductor
Diode (Correct answer)
Capacitor

Correct answer: Diode

A diode is a semiconductor device with two terminals that essentially acts as a one-way switch for current. It allows current to flow easily in one direction (forward bias) but severely restricts current from flowing in the opposite direction (reverse bias). This property is fundamental for converting alternating current (AC) to direct current (DC), a process called rectification, which is crucial for powering most electronic medical devices.

Question 30: The maximum allowable chassis leakage current for a patient-connected device in a general care area per NFPA 99 is:

1 mA
100 µA (Correct answer)
500 µA
10 µA

Correct answer: 100 µA

NFPA 99 allows a maximum chassis leakage current of 100 µA for patient-connected devices in general care (Category 2) areas.

Question 31: An op-amp in an inverting configuration has Rf = 100 kΩ and Rin = 10 kΩ. What is the voltage gain?

-0.1
-10 (Correct answer)
+0.1
+10

Correct answer: -10

Inverting amplifier gain = -Rf/Rin = -100kΩ/10kΩ = -10, where the negative sign indicates phase inversion.

Question 32: A surgical electrosurgical unit (ESU) causes burns at the dispersive electrode site. Which is the most likely cause?

Inadequate contact area or poor adhesion of the dispersive electrode (Correct answer)
Incorrect frequency setting
Broken active electrode pencil
Excessive generator output setting

Correct answer: Inadequate contact area or poor adhesion of the dispersive electrode

Burns at the dispersive (return) electrode site are most commonly caused by inadequate skin contact area or poor adhesion, increasing current density at that site.

Question 33: In medical electronics, what is the maximum allowable patient leakage current for a Type CF (cardiac floating) applied part under normal conditions per IEC 60601-1?

10 µA (Correct answer)
1000 µA
500 µA
100 µA

Correct answer: 10 µA

IEC 60601-1 limits patient leakage current for Type CF (cardiac floating) applied parts to 10 µA under normal conditions to protect against microshock hazards.

Question 34: Which section of the small intestine is the primary site for nutrient absorption?

Duodenum
Jejunum (Correct answer)
Cecum
Ileum

Correct answer: Jejunum

The jejunum has extensive villi and microvilli (brush border) and is the primary site for absorption of carbohydrates, proteins, and most nutrients.

Question 35: Which standard specifically governs the safety requirements for medical electrical equipment at the international level?

IEEE 802.11
OSHA 1910.303
NFPA 70
IEC 60601-1 (Correct answer)

Correct answer: IEC 60601-1

IEC 60601-1 is the international standard defining safety and essential performance requirements for medical electrical equipment.

Question 36: A patient connected to a mechanical ventilator triggers a persistent 'High Pressure' alarm. The patient is not coughing, and the tubing is free of kinks and water. What is the MOST likely operational issue or patient condition causing this alarm?

The patient's respiratory drive has ceased, leading to apnea.
An increase in airway resistance due to bronchospasm or a mucus plug. (Correct answer)
A partial disconnection of the ventilator circuit from the patient's endotracheal tube.
A significant leak in the endotracheal tube cuff.

Correct answer: An increase in airway resistance due to bronchospasm or a mucus plug.

A high-pressure alarm indicates that the ventilator requires more pressure than the preset limit to deliver the set tidal volume. This is typically caused by an obstruction or increased resistance in the airway. Bronchospasm (constriction of the airways) or a mucus plug physically narrows the passage, increasing resistance. A disconnection or cuff leak would cause a 'Low Pressure' alarm. Apnea would trigger a specific 'Apnea' or 'Low Respiratory Rate' alarm.

Question 37: Which blood vessel directly supplies oxygenated blood to the myocardium?

Aortic arch branches
Superior vena cava
Pulmonary artery
Coronary arteries (Correct answer)

Correct answer: Coronary arteries

The left and right coronary arteries arise from the aortic root and supply oxygenated blood directly to the myocardium.

Question 38: Which interference source is most likely to cause an artifact that mimics ventricular fibrillation on an ECG monitor?

60 Hz AC interference from a faulty electrode or lead wire (Correct answer)
Patient talking or coughing
Low battery in the wireless transmitter
Use of a non-standard electrode gel

Correct answer: 60 Hz AC interference from a faulty electrode or lead wire

Severe 60 Hz AC interference can produce a coarse, irregular waveform on the ECG that visually resembles ventricular fibrillation, requiring electrode and lead wire inspection.

Question 39: Which law in the United States regulates the sale and use of radiation-emitting electronic products including medical X-ray equipment?

The Medical Device Amendments Act of 1976
The Occupational Safety and Health Act (OSHA)
The Radiation Control for Health and Safety Act (RCHSA) (Correct answer)
The Safe Medical Devices Act (SMDA)

Correct answer: The Radiation Control for Health and Safety Act (RCHSA)

The Radiation Control for Health and Safety Act (RCHSA) authorizes the FDA to set and enforce performance standards for radiation-emitting electronic products, including X-ray equipment.

Question 40: Which standard covers requirements for medical device software lifecycle processes?

ISO 14971
IEC 62304 (Correct answer)
IEC 60601-1
ISO 9001

Correct answer: IEC 62304

IEC 62304 specifies life cycle requirements for medical device software development, maintenance, and risk management processes.

Question 41: What type of feedback is used in most biomedical amplifier designs to stabilize gain and improve linearity?

Regenerative feedback
No feedback
Negative feedback (Correct answer)
Positive feedback

Correct answer: Negative feedback

Negative feedback reduces gain but improves stability, linearity, bandwidth, and reduces distortion — essential characteristics for accurate biomedical signal amplification.

Question 42: Which of the following best describes 'risk priority number' (RPN) used in Failure Mode and Effects Analysis (FMEA)?

A regulatory classification assigned by the FDA
The product of severity, occurrence, and detectability ratings for a failure mode (Correct answer)
The total cost of potential failures over device lifetime
The number of reported adverse events divided by total devices in service

Correct answer: The product of severity, occurrence, and detectability ratings for a failure mode

RPN is calculated by multiplying severity × occurrence × detectability scores, helping prioritize which failure modes require the most urgent corrective action.

Question 43: In a pulse oximeter, which two wavelengths of light are used to differentiate oxyhemoglobin from deoxyhemoglobin?

550 nm and 850 nm
450 nm and 580 nm
660 nm and 940 nm (Correct answer)
780 nm and 1000 nm

Correct answer: 660 nm and 940 nm

Pulse oximeters use red light (~660 nm) and infrared light (~940 nm) because oxyhemoglobin and deoxyhemoglobin absorb these wavelengths at different ratios.

Question 44: Which organization publishes the Health Care Facilities Code that governs electrical safety requirements in US hospitals?

FDA
The Joint Commission
OSHA
NFPA (Correct answer)

Correct answer: NFPA

NFPA 99, Health Care Facilities Code, published by the National Fire Protection Association, sets US electrical safety standards for healthcare environments.

Question 45: When a biomedical technician replaces a lithium battery in an AED, the most critical final step before returning it to service is:

Recording the battery lot number
Updating the asset tag label
Performing a functional self-test and verifying ready indicator status (Correct answer)
Applying a new PM sticker

Correct answer: Performing a functional self-test and verifying ready indicator status

After any battery replacement in an AED, a functional self-test must be performed and the ready indicator verified before the device is returned to clinical use.

Question 46: Which hormone is produced by the adrenal medulla and plays a key role in the 'fight-or-flight' response?

Aldosterone
Epinephrine (Correct answer)
Cortisol
Insulin

Correct answer: Epinephrine

The adrenal medulla secretes epinephrine (adrenaline) and norepinephrine in response to sympathetic nervous system activation during stress.

Question 47: In a medical device's power supply circuit, an inductor is often used in conjunction with a capacitor. What is the primary function of the inductor in this filtering application?

To step up the voltage.
To store electrical charge.
To block direct current (DC).
To oppose changes in current. (Correct answer)

Correct answer: To oppose changes in current.

An inductor is a passive electronic component that stores energy in a magnetic field when electric current flows through it. Its fundamental property is to oppose any change in the electric current flowing through it. In power supply filters, this characteristic helps to smooth out the pulsating DC output after rectification, reducing ripple and providing a more stable DC voltage.

Question 48: Which sterilization method is most appropriate for heat-sensitive flexible endoscopes?

Ethylene oxide (EtO) or hydrogen peroxide gas plasma (Correct answer)
Dry heat oven at 160°C
Steam autoclave at 134°C
UV radiation chamber

Correct answer: Ethylene oxide (EtO) or hydrogen peroxide gas plasma

EtO and hydrogen peroxide gas plasma are low-temperature sterilization methods suitable for heat-sensitive endoscopes that cannot withstand steam autoclaving.

Question 49: In an ECG, a prolonged PR interval (>200 ms) indicates a conduction delay in which structure?

Bundle of His
Purkinje fibers
Sinoatrial (SA) node
Atrioventricular (AV) node (Correct answer)

Correct answer: Atrioventricular (AV) node

The PR interval represents the time from atrial depolarization to ventricular depolarization; prolongation indicates slowed conduction through the AV node (first-degree AV block).

Question 50: What is the function of a low-pass filter in biomedical signal processing?

Passes high frequencies and attenuates low frequencies
Passes a specific band of frequencies
Passes low frequencies and attenuates high frequencies (Correct answer)
Attenuates all frequencies equally

Correct answer: Passes low frequencies and attenuates high frequencies

A low-pass filter allows signals below its cutoff frequency to pass while attenuating higher frequency components.

Question 51: A defibrillator's energy output is measured during performance testing. For a 200 J selected energy, what delivered energy range is typically acceptable per IEC 60601-2-4?

±10% of selected energy
Exactly 200 J ±1 J
±5 J
±15% or ±4 J (whichever is greater) (Correct answer)

Correct answer: ±15% or ±4 J (whichever is greater)

IEC 60601-2-4 allows defibrillator delivered energy to be within ±15% of the selected energy or ±4 J, whichever is greater.

Question 52: Which prefix means 'within' or 'inside'?

Ecto-
Endo- (Correct answer)
Peri-
Exo-

Correct answer: Endo-

'Endo-' means within or inside, as in endoscopy (viewing inside the body).

Question 53: A patient is connected to a dialysis machine. This machine is performing the primary function of which anatomical organ?

Liver
Spleen
Kidneys (Correct answer)
Pancreas

Correct answer: Kidneys

The kidneys are the primary organs of the excretory system, responsible for filtering waste products from the blood and producing urine. A dialysis machine is an artificial replacement for this essential function when the kidneys fail.

Question 54: Why is thorough cleaning performed before sterilization or disinfection of medical instruments?

Cleaning alone achieves sterilization for most instruments
It activates the germicidal properties of the sterilizing agent
It neutralizes chemical residues from previous procedures
Organic debris can shield microorganisms and impair sterilant penetration (Correct answer)

Correct answer: Organic debris can shield microorganisms and impair sterilant penetration

Organic debris such as blood and tissue physically protects microorganisms from sterilants and blocks penetration of the sterilizing agent, making pre-cleaning essential.

Question 55: Which component of a flame atomic absorption spectrometer (AAS) produces the specific wavelength of light for the analyte being measured?

Hollow cathode lamp (Correct answer)
Monochromator
Flame burner
Photomultiplier tube

Correct answer: Hollow cathode lamp

The hollow cathode lamp contains the element of interest and emits its characteristic spectral lines used as the light source in AAS.

Question 56: Which physiological effect occurs when 60 Hz AC current in the range of 10–20 mA passes through the thorax?

Respiratory arrest without cardiac involvement
'Let-go' threshold exceeded, causing inability to release the conductor (Correct answer)
Tingling sensation only
Ventricular fibrillation

Correct answer: 'Let-go' threshold exceeded, causing inability to release the conductor

At 10–20 mA, sustained muscle tetany prevents voluntary release of the energized conductor, defining the 'let-go' threshold.

Question 57: A hospital-grade power strip differs from a consumer power strip primarily because it:

Has a higher surge protection rating
Has hospital-grade outlets with higher retention force and is listed for patient care areas (Correct answer)
Provides isolated power equivalent to an OR panel
Includes a built-in UPS battery backup

Correct answer: Has hospital-grade outlets with higher retention force and is listed for patient care areas

Hospital-grade power strips use high-retention outlets that resist accidental disconnection and meet UL 1363A standards for health care facilities, unlike consumer strips.

Question 58: What is the purpose of a pulse oximeter?

Analyze enzymes
Measure temperature
Check blood oxygen level (Correct answer)
Check glucose

Correct answer: Check blood oxygen level

A pulse oximeter is a non-invasive medical device used to measure a patient's oxygen saturation level in the blood (SpO2) and their pulse rate. It works by emitting light through a finger or earlobe and detecting the amount of light absorbed by oxygenated and deoxygenated hemoglobin. This quick and easy measurement provides crucial information about a patient's respiratory and circulatory status.

Question 59: Which type of muscle tissue is found in the walls of hollow organs like the bladder?

Striated muscle
Cardiac muscle
Smooth muscle (Correct answer)
Skeletal muscle

Correct answer: Smooth muscle

Smooth muscle is involuntary and lines hollow organs such as the bladder, uterus, and intestines.

Question 60: The concept of homeostasis is fundamental to physiology. Which of the following scenarios best illustrates this principle?

The process of breaking down food into nutrients in the digestive system.
The increase in heart rate and respiration during physical exercise.
The transmission of a nerve impulse from a sensory neuron to the brain.
The shivering of muscles in a cold environment to generate heat and maintain body temperature. (Correct answer)

Correct answer: The shivering of muscles in a cold environment to generate heat and maintain body temperature.

Homeostasis is the body's ability to maintain a stable internal environment despite external changes. Shivering is a physiological response to cold, where involuntary muscle contractions generate heat to counteract a drop in body temperature, thus maintaining internal stability.

Question 61: Which alarm condition on a ventilator should a biomedical technician investigate first because it poses immediate life threat?

High PEEP alarm
Tidal volume trending 5% low over 2 hours
Low pressure / disconnect alarm (Correct answer)
FiO2 slightly above set value

Correct answer: Low pressure / disconnect alarm

A low pressure or disconnect alarm indicates the patient may not be receiving ventilatory support, representing an immediate life threat requiring urgent response.

Question 62: In ultrasound imaging, axial resolution is primarily determined by:

Transducer frequency and pulse length (Correct answer)
Depth of the target structure
Transducer aperture size
Beam width at the focal zone

Correct answer: Transducer frequency and pulse length

Axial resolution (along the beam direction) depends on the spatial pulse length, which is determined by the transducer frequency and the number of cycles per pulse.

Question 63: Which type of medical gas outlet uses a pin-index safety system to prevent misconnection?

DISS (Diameter Index Safety System) outlets
Cylinder valve connections for small cylinders (Correct answer)
Pipeline bulk supply connections
Quick-connect wall outlets

Correct answer: Cylinder valve connections for small cylinders

The Pin Index Safety System (PISS) uses unique pin configurations on small medical gas cylinders to ensure only the correct gas regulator can be attached.

Question 64: The principle of event-related sterility asserts that a sterilized package:

Expires after a fixed period of 30 days regardless of storage conditions
Requires a color-coded tag system to indicate age-based sterility status
Remains sterile as long as packaging integrity is maintained, regardless of elapsed time (Correct answer)
Must be re-sterilized if stored for more than 6 months even if undamaged

Correct answer: Remains sterile as long as packaging integrity is maintained, regardless of elapsed time

Event-related sterility holds that a package remains sterile indefinitely as long as its integrity is preserved; sterility is compromised by events (damage, moisture, contamination), not time.

Question 65: Which ventilator parameter directly controls the fraction of time spent in inspiration versus total breath cycle time?

Tidal volume (Vt)
Peak Inspiratory Pressure (PIP)
Inspiratory:Expiratory ratio (I:E ratio) (Correct answer)
PEEP level

Correct answer: Inspiratory:Expiratory ratio (I:E ratio)

The I:E ratio defines the proportion of the respiratory cycle devoted to inspiration versus expiration, directly affecting gas distribution and hemodynamics.

Question 66: In capnography, an abnormally elevated ETCO2 value most often indicates:

Pulmonary embolism
Hyperventilation
Correct endotracheal tube placement failure
Hypoventilation or increased CO2 production (Correct answer)

Correct answer: Hypoventilation or increased CO2 production

Elevated end-tidal CO2 is typically caused by hypoventilation or conditions that increase CO2 production such as fever or sepsis.

Question 67: Under NFPA 99, receptacles in a Category 1 (critical care) patient care area must be:

Color-coded blue for identification purposes
Hospital-grade and connected to the equipment grounding system (Correct answer)
Twist-lock to prevent accidental disconnection
Standard duplex GFCI protected only

Correct answer: Hospital-grade and connected to the equipment grounding system

NFPA 99 requires hospital-grade receptacles in Category 1 areas to ensure reliable grounding and mechanical integrity under clinical conditions.

Question 68: A transcutaneous electrical nerve stimulator (TENS) unit produces a burning sensation for the patient during use. After ruling out technique error, the technician should:

Increase the pulse width to distribute current
Test output waveform and current amplitude against manufacturer specifications (Correct answer)
Replace the electrodes with larger ones immediately
Switch to a higher-frequency mode

Correct answer: Test output waveform and current amplitude against manufacturer specifications

A burning sensation may indicate output parameters outside of specifications; testing the actual output waveform and amplitude against manufacturer specs is the proper diagnostic step.

Question 69: The mitral valve is located between which two heart chambers?

Right atrium and right ventricle
Right ventricle and pulmonary artery
Left atrium and left ventricle (Correct answer)
Left ventricle and aorta

Correct answer: Left atrium and left ventricle

The mitral (bicuspid) valve separates the left atrium from the left ventricle.

Question 70: The femur articulates proximally with which structure?

Tibia
Patella
Acetabulum of the pelvis (Correct answer)
Fibula

Correct answer: Acetabulum of the pelvis

The head of the femur fits into the acetabulum of the hip bone, forming the hip joint.

Question 71: Which anatomical structure separates the thoracic cavity from the abdominal cavity and is the primary muscle of respiration?

Diaphragm (Correct answer)
Internal intercostal muscles
Transversus abdominis
External oblique muscle

Correct answer: Diaphragm

The diaphragm is a dome-shaped musculotendinous partition between the thorax and abdomen; its contraction increases thoracic volume to drive inspiration.

Question 72: A biomedical technician is servicing a diagnostic imaging system and finds a spreadsheet on the desktop containing a list of patient names and their medical record numbers. According to the Health Insurance Portability and Accountability Act (HIPAA), what is the most appropriate immediate action?

Make a copy of the file onto an encrypted drive as evidence of the breach.
Ignore the file, as the technician is not a clinical user of the system.
Delete the file immediately to prevent unauthorized access by others.
Report the finding to their immediate supervisor and the facility's designated Privacy Officer. (Correct answer)

Correct answer: Report the finding to their immediate supervisor and the facility's designated Privacy Officer.

The discovery of unsecured Protected Health Information (PHI) is a potential data breach under HIPAA. The technician's duty is not to independently decide how to handle the data (e.g., deleting or copying it) but to follow organizational policy by reporting the incident through the proper channels, which always includes their supervisor and the HIPAA Privacy/Security Officer.

Question 73: What is the first step in troubleshooting a non-functional medical device?

Replace the battery
Call the manufacturer
Check power and connections (Correct answer)
Disassemble the unit

Correct answer: Check power and connections

When troubleshooting a non-functional medical device, the first and most fundamental step is to check its power source and all connections. Many device malfunctions stem from simple issues like being unplugged, a tripped circuit breaker, a dead battery, or loose cables. Verifying these basic elements can quickly resolve common problems before moving on to more complex diagnostic steps.

Question 74: In the structural hierarchy of the human body, which level of organization is considered more complex than tissues?

Organs (Correct answer)
Cells
Molecules
Organ systems

Correct answer: Organs

The levels of structural organization in the body, from simplest to most complex, are: chemical (atoms/molecules), cellular, tissue, organ, organ system, and organism. Tissues are groups of similar cells that work together, and organs (like the heart or lungs) are composed of different types of tissues working together for a common function.

Question 75: What does an ECG machine measure?

Body temperature
Blood sugar
Heart electrical activity (Correct answer)
Lung function

Correct answer: Heart electrical activity

An Electrocardiogram (ECG or EKG) machine measures and records the electrical activity of the heart. It detects the tiny electrical changes on the skin that arise from the heart muscle's electrophysiological pattern during each heartbeat. This information is crucial for diagnosing various heart conditions, including arrhythmias, heart attacks, and other cardiac abnormalities.

Question 76: Which blood vessel carries oxygenated blood from the lungs to the heart?

Pulmonary vein (Correct answer)
Pulmonary artery
Superior vena cava
Aorta

Correct answer: Pulmonary vein

The pulmonary veins carry oxygen-rich blood from the lungs back to the left atrium of the heart.

Question 77: An IFU (Instructions for Use) for a medical device must be provided in which language for devices sold in the United States?

English only (Correct answer)
English and any language spoken by more than 5% of the local population
English, with translations required if the device is sold in multilingual markets
English and Spanish

Correct answer: English only

FDA requires that IFUs for devices marketed in the US be in English, though manufacturers may include additional languages.

Question 78: What is the term for the double-layered membrane surrounding the heart?

Pericardium (Correct answer)
Perichondrium
Pleura
Peritoneum

Correct answer: Pericardium

The pericardium is the fibrous sac enclosing the heart, consisting of two layers that reduce friction.

Question 79: A biomedical technician suspects RF interference is affecting a telemetry monitoring system. Which action is most appropriate initially?

Replace all telemetry transmitters immediately
Identify and document the interference source and notify the clinical engineering and IT teams (Correct answer)
Turn off all wireless devices on the floor
Rewire the nursing station network

Correct answer: Identify and document the interference source and notify the clinical engineering and IT teams

The first step is to identify and document the RF interference source systematically and escalate to appropriate teams before taking corrective action.

Question 80: Why is proper installation critical in biomedical equipment?

To match the room design
To make it look good
To reduce taxes
To ensure function and safety (Correct answer)

Correct answer: To ensure function and safety

Proper installation is absolutely critical for biomedical equipment because it directly impacts both the device's intended function and the safety of patients and users. Incorrect installation can lead to malfunctions, inaccurate readings, electrical hazards, or even physical instability. Adhering to manufacturer guidelines and safety standards during installation ensures the equipment operates reliably and safely within the clinical environment.

Question 81: In an ECG machine, the CMRR (Common Mode Rejection Ratio) specification is important because it:

Increases signal amplitude
Amplifies differential signals only
Filters high-frequency noise
Rejects 60 Hz power line interference (Correct answer)

Correct answer: Rejects 60 Hz power line interference

High CMRR allows the differential amplifier to reject common-mode noise such as 60 Hz interference from power lines while amplifying the ECG signal.

Question 82: Which of the following best describes the purpose of a 'load test' on an uninterruptible power supply (UPS)?

Confirms the UPS can deliver rated output power for a specified duration (Correct answer)
Verifies input voltage regulation under steady-state conditions
Tests the surge suppression circuitry
Checks the battery charger input current

Correct answer: Confirms the UPS can deliver rated output power for a specified duration

A load test applies rated or specified load to the UPS to verify it sustains output power for the required backup duration.

Question 83: A biomedical technician is calibrating an intraocular pressure monitor. Which fluid is measured indirectly by this device?

Vitreous humor
Aqueous humor (Correct answer)
Perilymph
Cerebrospinal fluid

Correct answer: Aqueous humor

Intraocular pressure is largely determined by the production and drainage of aqueous humor in the anterior segment of the eye.

Question 84: Which component in an electrosurgical unit (ESU) converts standard AC line power into the high-frequency RF current used for cutting and coagulation?

Isolation transformer
Resonant tank circuit (Correct answer)
Bipolar footswitch relay
Ground fault interrupter

Correct answer: Resonant tank circuit

The resonant tank circuit (oscillator) in an ESU generates high-frequency RF output (typically 300 kHz–5 MHz) from the rectified DC supply.

Question 85: Which fluid compartment contains approximately two-thirds of total body water in an adult?

Interstitial fluid
Intravascular fluid
Intracellular fluid (Correct answer)
Transcellular fluid

Correct answer: Intracellular fluid

Intracellular fluid (ICF) accounts for about 67% of total body water (~28 L in a 70 kg adult), found within all body cells.

Question 86: In the context of electrical safety, 'macroshock' is defined as current entering the body:

Via inductive coupling only
Directly into the heart via a catheter
Through a broken ground conductor
Through the intact skin surface (Correct answer)

Correct answer: Through the intact skin surface

Macroshock refers to electric current entering and exiting through the skin surface, requiring higher currents (mA range) to cause fibrillation.

Question 87: Which NFPA 99 category designation applies to spaces where failure of equipment is likely to cause major injury or death to patients or caregivers?

Category 4
Category 1 (Correct answer)
Category 2
Category 3

Correct answer: Category 1

NFPA 99 Category 1 (formerly 'critical care') covers areas where equipment failure could result in major injury or death.

Question 88: In a hemodialysis machine, the conductivity monitor of the dialysate circuit is critical because it detects:

Transmembrane pressure exceeding safe limits
Incorrect electrolyte concentration that could cause patient harm (Correct answer)
Air bubbles in the blood circuit
Blood leak into the dialysate

Correct answer: Incorrect electrolyte concentration that could cause patient harm

Conductivity correlates directly with dissolved electrolyte (sodium) concentration; a conductivity alarm stops dialysate delivery to prevent hypo- or hypernatremia.

Question 89: When setting up a continuous passive motion (CPM) device post-knee surgery, which parameter is adjusted FIRST before range-of-motion settings?

Speed of cycling
Flexion angle limit
Limb length/segment alignment (Correct answer)
Pause time at end range

Correct answer: Limb length/segment alignment

Proper limb segment alignment in the CPM device must be confirmed first to ensure the mechanical joint axis matches the anatomical joint axis and prevent injury.

Question 90: When comparing biphasic and monophasic defibrillators, which of the following is a key operational advantage of biphasic technology?

Biphasic defibrillators always deliver a higher maximum energy shock (e.g., 360 Joules).
Biphasic waveforms are less effective but have a longer battery life.
They require significantly less energy to achieve the same or higher efficacy, reducing potential cardiac damage. (Correct answer)
Monophasic technology is newer and provides more detailed post-shock ECG analysis.

Correct answer: They require significantly less energy to achieve the same or higher efficacy, reducing potential cardiac damage.

Biphasic defibrillators send the current in two directions, which allows them to terminate arrhythmias with significantly lower energy levels (e.g., 120-200J) compared to monophasic devices (which may go up to 360J). This lower energy reduces the risk of skin burns and damage to the heart muscle. Biphasic technology is the current standard and has largely replaced the older monophasic technology.

Question 91: In a pulse oximeter, photodetectors measure light absorption at two wavelengths. Which wavelengths are typically used?

660 nm and 940 nm (Correct answer)
450 nm and 550 nm
750 nm and 850 nm
500 nm and 700 nm

Correct answer: 660 nm and 940 nm

Pulse oximeters use red light (~660 nm) and infrared light (~940 nm) because oxyhemoglobin and deoxyhemoglobin have distinct absorption differences at these wavelengths.

Question 92: Under HIPAA, a Business Associate Agreement (BAA) is required when a third-party vendor does which of the following?

Creates, receives, maintains, or transmits PHI on behalf of a covered entity (Correct answer)
Manufactures pharmaceutical supplies
Provides general IT support with no access to patient data
Sells medical equipment to a hospital

Correct answer: Creates, receives, maintains, or transmits PHI on behalf of a covered entity

A BAA is required whenever a vendor handles Protected Health Information (PHI) on behalf of a HIPAA-covered entity.

Question 93: An electrically susceptible patient (ESP) is one who has a direct conductive pathway to the heart. The ventricular fibrillation threshold for such a patient is approximately:

500 µA
1 mA
100 µA
10–20 µA (Correct answer)

Correct answer: 10–20 µA

Current as low as 10–20 µA applied directly to the myocardium can trigger ventricular fibrillation in electrically susceptible patients.

Question 94: When calibrating an invasive blood pressure transducer, zeroing the transducer at the level of the phlebostatic axis compensates for:

Electrical offset in the Wheatstone bridge
Damping coefficient variation
Catheter tip resonance artifact
Hydrostatic pressure error due to fluid column height (Correct answer)

Correct answer: Hydrostatic pressure error due to fluid column height

Zeroing at the phlebostatic axis eliminates hydrostatic pressure added by or subtracted from the fluid column between the transducer and the patient's heart.

Question 95: Which approach best demonstrates mastery of laboratory equipment in CABT practice?

Following procedures without understanding
Applying principles to novel situations with sound judgment (Correct answer)
Relying entirely on technology
Avoiding complex scenarios

Correct answer: Applying principles to novel situations with sound judgment

True mastery involves understanding underlying principles well enough to apply them to new and unfamiliar situations with professional judgment.

Question 96: A CT system's ability to distinguish between two objects of similar density is described by which performance metric?

Spatial resolution (MTF)
Low-contrast detectability (Correct answer)
Noise power spectrum
Slice sensitivity profile

Correct answer: Low-contrast detectability

Low-contrast detectability (or contrast resolution) describes the system's ability to differentiate structures with small differences in X-ray attenuation.

Question 97: When storing sterile packages after processing, which factor is most critical for maintaining sterility?

Keeping packages in a humidity-controlled environment above 60% RH
Maintaining packaging integrity and protecting from moisture and physical damage (Correct answer)
Re-sterilizing packages stored for more than 30 days regardless of condition
Storing in a temperature-controlled refrigerator below 20°C

Correct answer: Maintaining packaging integrity and protecting from moisture and physical damage

Sterility is event-related; it depends on the integrity of the packaging rather than time, so intact, undamaged, dry packaging preserves sterility indefinitely.

Question 98: A technician is working on a portable insulin pump. The compact size and low power consumption of the device's control circuitry are critical design features. These are made possible primarily by the use of which technology?

High-capacity resistors
Electromechanical relays
Integrated circuits (Semiconductors) (Correct answer)
Vacuum tubes

Correct answer: Integrated circuits (Semiconductors)

Integrated circuits (ICs), built from semiconductor materials, are the foundation of modern electronics, enabling the miniaturization and power efficiency required for portable and implantable medical devices like insulin pumps and pacemakers. They allow for complex circuits with millions or billions of transistors, amplifiers, and other components to be placed on a single tiny chip.

Question 99: When a biomedical engineer reviews a ventilator parameter labeled 'FRC,' what physiological measurement does this represent?

The volume of air inspired in one normal breath
The maximum volume of air exhaled after maximum inhalation
The volume of air remaining in the lungs after a normal passive exhalation (Correct answer)
The maximum volume of air that can be inspired after a normal inhalation

Correct answer: The volume of air remaining in the lungs after a normal passive exhalation

Functional Residual Capacity (FRC) is the volume of gas remaining in the lungs after a normal passive expiration, combining expiratory reserve volume and residual volume.

Question 100: A hospital bed's nurse-call function is inoperative after repairs. What document should the technician consult to verify wiring?

The manufacturer's service/wiring diagram (Correct answer)
The Joint Commission survey report
The biomedical work order log
The hospital formulary

Correct answer: The manufacturer's service/wiring diagram

The manufacturer's service manual and wiring diagram provides authoritative information on correct wiring, connectors, and signal paths for the nurse-call circuit.

Question 101: The half-value layer (HVL) of an X-ray beam is defined as the thickness of material that reduces beam intensity by:

90%
50% (Correct answer)
25%
75%

Correct answer: 50%

The HVL is the thickness of a specified attenuator (typically aluminum) that reduces the X-ray beam intensity to exactly half (50%) of its original value.

Question 102: Which anatomical term describes the movement of a limb away from the midline of the body?

Adduction
Abduction (Correct answer)
Inversion
Circumduction

Correct answer: Abduction

Abduction is the movement of a body part away from the midline, while adduction moves it toward the midline.

Question 103: What is the time constant (τ) of an RC circuit with R = 10 kΩ and C = 100 µF?

0.1 seconds
1 second (Correct answer)
100 seconds
10 seconds

Correct answer: 1 second

τ = RC = 10,000 Ω × 0.0001 F = 1 second.

Question 104: Electromagnetic interference (EMI) from a nearby electrosurgical unit most commonly affects which monitoring device by inducing artifact that mimics the signal of interest?

ECG rhythm display (Correct answer)
Pulse oximeter plethysmographic waveform
End-tidal CO2 waveform
Non-invasive blood pressure reading

Correct answer: ECG rhythm display

ESU RF energy couples into ECG lead wires, which act as antennas, producing artifact that obscures the cardiac signal during electrosurgical activation.

Question 105: In an EEG amplifier, why is a notch filter at 60 Hz commonly used?

To prevent electrode polarization
To increase signal-to-noise ratio across all frequencies
To amplify brain wave frequencies
To eliminate power line interference from the signal (Correct answer)

Correct answer: To eliminate power line interference from the signal

A 60 Hz notch filter selectively attenuates power line frequency interference while passing the EEG signal frequencies (0.5–100 Hz).

Question 106: A bispectral index (BIS) monitor primarily measures which physiological parameter?

Cerebral perfusion pressure
Depth of anesthesia or sedation via processed EEG (Correct answer)
Cardiac output via echocardiography
Degree of neuromuscular blockade

Correct answer: Depth of anesthesia or sedation via processed EEG

The BIS monitor uses a processed EEG algorithm to generate a numeric index (0–100) that reflects the patient's level of consciousness or depth of anesthesia.

Question 107: In Certified Associate in Biomedical Technology, what is the PRIMARY purpose of conducting an initial assessment?

To fulfill administrative paperwork requirements
To generate documentation for billing purposes
To demonstrate the assessor's expertise
To establish a baseline and identify needs for appropriate action (Correct answer)

Correct answer: To establish a baseline and identify needs for appropriate action

The initial assessment establishes a baseline of current conditions and identifies specific needs. This foundational information guides all subsequent decisions, planning, and interventions.

Question 108: What is the primary purpose of a grid in diagnostic radiography?

To collimate the primary beam
To reduce scattered radiation reaching the detector (Correct answer)
To filter low-energy photons from the tube
To increase patient dose

Correct answer: To reduce scattered radiation reaching the detector

A radiographic grid is placed between the patient and detector to absorb scattered radiation, improving image contrast.

Question 109: A 12-bit ADC with a 5V reference voltage has a resolution of approximately:

1.22 mV (Correct answer)
12.2 mV
0.122 mV
122 mV

Correct answer: 1.22 mV

Resolution = Vref / 2^n = 5V / 4096 ≈ 1.22 mV per step for a 12-bit ADC.

Question 110: ISO 13485 is a quality management standard specifically designed for:

Clinical laboratory operations
Organizations in the medical device supply chain (Correct answer)
General manufacturing industries
Hospital infection control programs

Correct answer: Organizations in the medical device supply chain

ISO 13485 specifies requirements for a quality management system where an organization needs to demonstrate its ability to provide medical devices and related services.

Question 111: Under the Safe Medical Devices Act (SMDA), which facilities are required to report device-related adverse events to the FDA?

Manufacturers and importers only
Only device manufacturers
User facilities such as hospitals and nursing homes (Correct answer)
Only outpatient clinics and ambulatory surgery centers

Correct answer: User facilities such as hospitals and nursing homes

The SMDA requires user facilities, including hospitals and nursing homes, to report device-related deaths and serious injuries to the FDA and/or manufacturer.

Question 112: The term 'patient environment' or 'patient care vicinity' as defined by NFPA 99 refers to a space extending:

3 feet horizontally and 5 feet vertically from the patient's head
10 feet in all directions from the patient
6 feet horizontally and 7.5 feet vertically from the patient bed edge (Correct answer)
The entire patient room floor area

Correct answer: 6 feet horizontally and 7.5 feet vertically from the patient bed edge

NFPA 99 defines the patient care vicinity as a zone 6 feet horizontally from the bed edge and up to 7.5 feet above the floor.

Question 113: Which of the following accurately describes the function of the blood-brain barrier (BBB)?

It is formed by neurons in the cerebral cortex
It selectively restricts the passage of substances between blood and brain tissue (Correct answer)
It prevents all nutrients from entering the brain
It regulates the flow of cerebrospinal fluid between ventricles

Correct answer: It selectively restricts the passage of substances between blood and brain tissue

The BBB, formed by tight junctions between brain capillary endothelial cells and supported by astrocyte endfeet, selectively controls what enters brain tissue.

Question 114: Which federal law established the framework for regulating health information technology and incentivizing adoption of electronic health records (EHRs)?

FDA Safety and Innovation Act (2012)
HITECH Act (2009) (Correct answer)
Affordable Care Act (2010)
HIPAA (1996)

Correct answer: HITECH Act (2009)

The HITECH Act of 2009 established programs to incentivize meaningful use of EHRs and strengthened HIPAA privacy and security enforcement.

Question 115: A patient-connected medical device shows a leakage current reading of 600 µA under normal condition (NC). Per NFPA 99 and AAMI standards, this reading is:

Within limits for body surface contact (BF) devices only
Exceeding the 500 µA limit and the device should be removed from service (Correct answer)
Acceptable for all patient-connected devices
Only acceptable if the device is isolated from ground

Correct answer: Exceeding the 500 µA limit and the device should be removed from service

AAMI/ANSI ES60601-1 and NFPA 99 limit chassis leakage current for patient-care equipment to 500 µA under normal conditions; 600 µA exceeds this limit.

Question 116: Which lobe of the brain is primarily responsible for processing visual information?

Frontal lobe
Occipital lobe (Correct answer)
Temporal lobe
Parietal lobe

Correct answer: Occipital lobe

The occipital lobe at the rear of the brain is the primary visual processing center.

Question 117: Which documentation is essential when working with imaging systems in CABT?

General descriptions without specifics
Detailed technical specifications and as-built diagrams (Correct answer)
Only verbal notes
Marketing materials

Correct answer: Detailed technical specifications and as-built diagrams

Detailed technical specifications and as-built diagrams provide the accurate reference information needed for maintenance and troubleshooting.

Question 118: When performing routine safety testing on a patient-connected medical device, the maximum allowable patient leakage current under normal conditions (NC) for a Type CF device is:

100 µA
500 µA
50 µA
10 µA (Correct answer)

Correct answer: 10 µA

IEC 60601-1 specifies that Type CF devices (intended for direct cardiac application) have a maximum patient leakage current of 10 µA under normal conditions.

Question 119: Which nuclear medicine imaging modality provides functional 3D images by detecting pairs of annihilation photons?

SPECT
Gamma camera imaging
PET (Correct answer)
Planar scintigraphy

Correct answer: PET

PET (Positron Emission Tomography) detects coincident 511 keV annihilation photons produced when a positron meets an electron, enabling 3D functional imaging.

Question 120: A gas chromatograph (GC) used in toxicology shows baseline noise. Which component is most likely responsible?

Carrier gas supply
Sample injector port
Column oven fan
Detector or detector contamination (Correct answer)

Correct answer: Detector or detector contamination

Detector contamination or detector malfunction is the most common cause of elevated baseline noise in gas chromatography systems.

CABT Certified Associate in Biomedical Technology Exam

The CABT Certified Associate in Biomedical Technology Exam validates foundational competencies in biomedical equipment technology, including installation, maintenance, troubleshooting, anatomy, electronics, patient safety, and healthcare regulations.

120

Questions

120 min

Time Limit

70%

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